MENTOR’S #DEER POPULATION: Part IV THE OBJECTIONS TO CULLING

Until a few of years ago, I couldn’t understand how anyone could commit what I thought of as Bambicide. What kind of deviant species were deer hunters, anyway? Why not sterilize or relocate deer to thin out their herds?

I now recognize and admit to having been a Bambiholic, a Woman Who Loved Bambi Too Much, an addict for whom no twelve-step program existed.

My recovery began when I became involved with conservation groups in the area.

That was when I realized that people antagonistic to my beliefs were highly educated and respected naturalists, conservationists and even curators at the Cleveland Museum of Natural History.

These people taught me about the severity of the impact of deer over-population and why my pet solutions weren’t solutions at all.

I also learned my pet fear of bullets and arrows whizzing around Mentor wasn’t a valid fear. Sharpshooters must pass a qualifying test before they’re permitted to hunt deer for a city or natural area. And they generally aim down from platforms in trees in restricted areas, not across yards.

It’s thanks to these people that I’m now a recovering Woman Who Loved Bambi Too Much.

For my series of blogs, I’ve interviewed Dave Hromco, Assistant Director of Public Works for the City of Solon, Mike Watson, Conservation Biologist at The Holden Arboretum, John Oros, Operations Director for Geauga Park District and Rick Tyler, Senior Natural Resource Manager for Cleveland Metroparks.

They’ve all read and approved information I’ve printed that relates to their experiences in successfully controlling the deer population in their areas.

My chief mentor is Dr Thomas Rooney of Wright State University in Dayton. He’s received awards for his numerous conservation achievements. Rooney is recognized as an expert, maybe the expert, consultant in managing deer populations both here in the US and abroad.

Recently I read of two objections claiming deer culling was unsuccessful because of deer migration and because of a rebound effect. These were objections I’d neither considered nor had heard of. Both were used to explain why the City of Solon’s culling practice was a failure and had resulted in a higher deer population.

Here’s what I found in several articles in the Chagrin Solon Sun: Solon hired a private contractor at $100,000/year to cull deer beginning in 2003. The deer population was approximately 1500 and deer-car accidents stood at 165.

By 2008, Solon had only about 405 deer and 45 deer-car accidents. They also had tulips and hosta lilies growing unmolested in the community. The culling program was successful.

But in 2010, the estimate spiked to 694 deer with 64 deer-car accidents. And this year, residents report that they and their pets are being attacked by deer.

Why the spike? Because in 2009, fiscal short-falls forced the city to discontinue culling.

Currently, the city is considering certifying volunteers to cull, as do other cities and natural areas such as the Geauga Park District.

Still, though, I wondered about the validity of deer migration and rebound effect objections. I turned to Rooney for an evaluation. I’ve cut and pasted his email responses to the two claims.

1. Culling is futile because neighboring deer will migrate in to fill up the gap.

Rooney’s response:
“The statement that deer will move in is only half true, and it is a half-truth that works in your favor.

“The key to understanding deer movements lies in understanding differences between the sexes. Female deer tend to establish territories near their mothers. In fact, you get matrilineal lines of deer in particular areas–grandmothers, mothers, and daughters forming concentric rings away from a center. This even has a name–the rose petal theory. These animals are not likely to move into new areas that are ‘opened up’ by culling.’

“Then there are the boys. Male deer are interested in establishing territories where they have access to food (to build big sexy antlers) and lady deer. These animals will likely move in from neighboring communities. However, if females are sparse, most male deer will probably not linger long. You will probably end up with young males that are at the low end of the pecking order establishing, but I suspect culling will still result in an overall density reduction.

“More broadly, you might argue that several communities have successfully reduced their deer populations through culling, achieving their goals that were measurable in terms of Lyme disease transmission reduction, fewer vehicle accidents, and fewer complaints from homeowners. I think said Mentor council member would be hard-pressed to find a community that developed a culling program that ended in failure because ‘deer from next door moved in.’ I am not aware of a single community with that experience.”

The Rebound Effect. After culling, there’ll be so much more food for the remaining deer that they’ll reproduce more. The result will be even more deer than before.

Rooney’s response:

“I’m not sure where your councilman is getting his information, but again it seems rooted in sound logic based on faulty assumptions (and therefore incorrect), instead of actual evidence. If there is a single community that experienced this rebound effect, I would like to know about it–it would be both interesting and instructive to me. However, this does not happen. Food limitation does not limit deer reproduction in the Cleveland area. Deer typically have 2 (sometimes 3) offspring, just like humans have 1 or sometimes more offspring. No additional amount of food can increase that–it is controlled by genetics. Likewise, during weaning, a mom can only eat so much food and convert it into milk–an additional million trilliums per acre will not boost fawn survival.”

Rooney is an unbiased scientist. I know he’s serious when he says he’d like to study a community that’s experienced a rebound effect. If you have information about such a community, you can contact him at the URL below: